LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Subaru >> 2001 >> Outback Base, Standard >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 2.2L & 2.5L >> Diagnostic Tests >> DTC P0121: Throttle Position (TP) Sensor Circuit Range/Performance Problem (High Input) - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC P0121: Throttle Position (TP) Sensor Circuit Range/Performance Problem (High Input) - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport

  1. Perform basic diagnostic procedure. See BASIC DIAGNOSTIC PROCEDURE . If DTC P0107, P0108, P0122 and/or P0123 exist, diagnose those DTCs. Do not diagnose DTC P0121. If DTC P0121 is only DTC set, go to next step.
  2. Start engine. Using scan tool, observe intake manifold absolute pressure. If pressure reads more than 15.75 in. Hg, replace intake manifold absolute pressure sensor. If pressure does not read more than 15.75 in. Hg, replace throttle position sensor. Clear memory and perform verification procedure. See CLEARING DIAGNOSTIC TROUBLE CODES  and VERIFICATION PROCEDURE  .